Fixed #24829 -- Allowed use of TemplateResponse in view error handlers.

1 files changed, 9 insertions, 0 deletions

diff --git a/django/core/handlers/base.py b/django/core/handlers/base.py
index cad2ba2a60..04c8f79180 100644
--- a/django/core/handlers/base.py
+++ b/django/core/handlers/base.py
@@ -113,6 +113,9 @@ class BaseHandler(object):
         urlconf = settings.ROOT_URLCONF
         urlresolvers.set_urlconf(urlconf)
         resolver = urlresolvers.RegexURLResolver(r'^/', urlconf)
+        # Use a flag to check if the response was rendered to prevent
+        # multiple renderings or to force rendering if necessary.
+        response_is_rendered = False
         try:
             response = None
             # Apply request middleware
@@ -174,6 +177,7 @@ class BaseHandler(object):
                             "HttpResponse object. It returned None instead."
                             % (middleware_method.__self__.__class__.__name__))
                 response = response.render()
+                response_is_rendered = True
 
         except http.Http404 as exc:
             logger.warning('Not Found: %s', request.path,
@@ -246,6 +250,11 @@ class BaseHandler(object):
 
         response._closable_objects.append(request)
 
+        # If the exception handler returns a TemplateResponse that has not
+        # been rendered, force it to be rendered.
+        if not response_is_rendered and callable(getattr(response, 'render', None)):
+            response = response.render()
+
         return response
 
     def handle_uncaught_exception(self, request, resolver, exc_info):